Students will learn the main fea-

tures of East River invertebrates

and how to use a dichotomous key

and taxonomy tree to properly

identify them.

4-8

25-45 minutes

Dichotomous key and mystery

organism cards (provided)

Taxonomy worksheet, student

and teacher copy (provided)

Whiteboard & marker

Tape

Plants and animals are classified into

groups called taxons. There are 8 taxon-

omy ranks: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Domain is the broadest and species is

the most specific title given to an organ-

ism. The eastern oyster is a species. All oysters, however, can be grouped into

broader groups, such as the kingdom

Animalia or phylum Mollusca.

Animals are often characterized based

on other similarities. For example, all

animals without a backbone are called

invertebrates. An oyster is not only an

invertebrate, but also a bivalve. A bi-valve is an animal that has two shells

attached by a hinge. Other examples of

bivalves include clams, mussels, and

scallops. Snails are considered univalves because they have a shell that is one

single piece. Snails and all bivalves be-

long to the same phylum, Mollusca.

Crabs and shrimp are also invertebrates,

but are less related to mollusks because

they have exoskeletons rather than true shells.

A classification chart can help you visu-alize the taxonomy of different marine

organisms and how closely they are re-

lated. To identify unknown species,

scientists use dichotomous keys. This tool provides a set of descriptions, each

leading to a result or further choices

until a proper classification is reached.

Activity 1:

1. Print and cut mystery cards (1 set has 17 different cards). The number sets to print will

depend on class size. All students should have at least one card to work with. To make

easier, you may want to group students with 1 card per group. To make more challeng-

ing, give each student or group multiple cards. Consider laminating for extended use.

2. Have a whiteboard or wall available to hang up all mystery invertebrate photos if class

will be sorting or labeling organisms together.

Activity 2:

1. Print a blank copy of the taxonomy worksheet for each student and one teacher copy

with answers.

2. If desired, use a whiteboard to recreate the taxonomy chart on the board. 1

1. Ask students if they can define an invertebrate. A: An animal without a backbone or spine. Ask students to try to find and feel their backbone or their friend’s. An animal with a backbone is called a verte-

brae. Can you think of any other animals, besides humans, that have a backbone or spine? A: Mam-

mals, birds, reptiles, fish.

2. Can you think of any examples of animals that are invertebrates? A: Insects, crabs, snails, clams, jellyfish,

etc. A large majority (about 97%) of animals are actually invertebrates! All animals with shells are in-vertebrates.

3. Tell students they will be taking a field trip to Brooklyn Bridge Park where they will be learning about

a very special invertebrate called the eastern oyster. Oysters are a type of bivalve. The prefix bi– means two. Therefore, a bivalve is an animal with two shells or valves. Oysters live attached to each other in

large groups to form a reef. An oyster reef creates an excellent habitat for many other East River inver-

tebrates.

1. During your trip to Brooklyn Bridge Park, students will examine the oysters in our oyster gardens and

identify any other organisms found living amongst the oysters. Oysters can be a delicious meal for

fish, a type of vertebrate often found near oyster reefs. Some invertebrates enjoy feasting on oysters

too. Oyster reefs also provide great habitat and protection for small invertebrates. Have students

practice identifying the names of East River invertebrates they may see by using the provided photos

and dichotomous key.

2. Give each student one mystery invertebrate card and one copy of the dichotomous key. You could

alternatively separate students into groups, providing one or more mystery cards to each group.

3. Students should start at question one in the dichotomous key and continue following the numbered

directions until reaching a species identification.

4. Check students’ guesses or write the names of all the organisms on the whiteboard and have students

tape their organism to the correct name once they have determined it based on the dichotomous key.

5. Consider having students take turns presenting to the class their organism and some facts they

learned about it, or go over answers on the board with the entire class.

MODIFIED ACTIVITY FOR YOUNGER STUDENTS : If reading and following the dichotomous key is too

difficult for children, consider having students work together to sort all animals into groups based physical features

that are easily visible in the photos. For example, students can group animals by “shelled” vs “not shelled.”

MODIFIED ACTIVITY (VERSION 2): Put 4 columns on the board with the phyla listed. Next, have students

match their animal to the appropriate phylum (Phyla are on each card, under the photo) Together you can work

with the class to observe what the all animals in each group (phylum) have in common. I.e. the animals in the phylum

Annelida are worm-like. Most of the animals in Arthropoda are crabs. All the animals in Mollusca have shells. Ask students if they recognize any other similarities and differences!

2

Classifying Invertebrates by Francine Galko (Gr. 3-5)

The Big Oyster: History on the Half Shell by Mark Kurlansky

Shell (Eyewitness Books) by Dorling Kindersley

Billion Oyster Project

https://billionoysterproject.org

Arkive: Marine Invertebrates

http://www.arkive.org/invertebrates-marine/

Estuaries 101 Curriculum

https://coast.noaa.gov/estuaries/curriculum/

Ocean Portal (Lesson plans and info on marine invertebrates)

http://ocean.si.edu/

1. For older groups, have students apply what they know about

all the newly identified species to fill in the classification

chart. Reminder: the phylum for each species is listed on each mystery card; additional hints to help properly place

each organism are also mentioned on the cards.

2. Give each student a copy of the blank taxonomy classification

chart.

3. Be sure to direct students’ attention to the key in the bottom

left corner. The key will help identify which boxes in the tree

represent kingdom, phylum, and class for each organism.

Note: The diagram provided only includes a sampling of invertebrates

found in the East River. This taxonomy tree is not inclusive of all the

phylum, orders, and species that exist.

3

Carapace: the hard upper shell of a turtle, crusta-cean, or arachnid.

Classification Chart: An arrangement of items to help illustrate relations. In the science field, this

may also be known as a classification tree or phylo-

genetic tree. These charts will usually depict species

evolution or taxonomic ranks.

Crustacean: A subphylum of Arthropods. Mostly includes marine organisms such as crabs, lobsters,

crayfish, shrimp, krill, and barnacles. Crustaceans

have a segmented body and a exoskeleton.

Bivalve: Marine mollusks (clams, oysters, or scal-lops) that have a 2-valved hinged shell, are usually

filter feeders, and lack a distinct head.

Dichotomous Key: A tool for identifying items in the natural world, such as trees, mammals, rocks,

or fish. Keys consist of a series of choices that lead

the user to the correct name of a given item.

Estuary: A partly enclosed coastal body of brackish water with one or more rivers or streams flowing

into it, and with a free connection to the open sea.

Exoskeleton: a rigid external covering for the body in some invertebrate animals, especially arthro-

pods, providing both support and protection. Un-

like a shell which grows with the animal, and exo-

skeleton is shed once outgrown enabling the ani-

mal to expand in size before a new exoskeleton

hardens around the organism.

Invertebrate: An animal lacking a backbone.

Oyster Garden: A cage containing live oysters that are monitored by students or scientists.

Mollusk: An phylum of invertebrates that includes snails, slugs, oysters, and clams. They have a soft,

unsegmented body . Many mollusks have a shell.

Oyster Reef: A group of oysters growing together under the water.

Salinity: The saltiness or dissolved salt content of a body of water.

Sessile: Fixed in one place; immobile.

Shell: A hard, protective outer layer of an organ-ism. Seashells belong specifically to marine animals

and are made of calcium carbonate.

Taxonomy: The defining and naming of biologi-cal organisms into groups on the basis of shared characteristics. Organisms are grouped together into taxa (singular: taxon) and these groups are given a taxonomic rank. The ranks are domain, kingdom, phylum, class, order, family, genus, and species. Univalve: Mollusks that have one shell or valve. Vertebrae: An animal with a backbone.

4

Reading Informational Text

Speaking and Listening

Literacy in Technical Subjects

Literacy in Science

Counting and Cardinality

Measurement and Data

Ratios & Proportional Relation-

ships

Diversity of Life

Animal Diversity

2, 3, MS, HS: Interdependent Rela-

tionships in Ecosystems

4, MS, HS. Structure, Function

5, MS, HS. Matter and Energy in

Ecosystems